Marley is an artist, or, perhaps, an artisan. She sees it as her duty to help humans find meaning in their lives by bringing those lives to an end at that time which she feels is most appropriate. Mortals are inherently finite creations, and to extend their being over too much time dilutes them and risks spreading the actual substance of their lives thin. It is on this criteria that Marley decides how long each human should live, and when the time comes, she efficiently sends them on to their next stage of existence.

Marley is about three hundred years old, and she tends to dress and act as though she were a gentrified male of the seventeenth century. Her clothes are usually some form of loose black suit, but the effect is prevented from becoming too perfect by her oversized, crooked top hat, and the sharp but unrefined pocketknife that she carries with her at all times.